Both Geisler and Turek repeat the slogan “the atheist must borrow X from theism” (e.g., logic, morality, agency, mathematics, etc.) in a dozen of variations, all making assertions about metaphysical issues that allegedly cannot be explained under the hypothesis of naturalism, and require the existence of God. Of course, actual naturalist philosophers, such as Jack Ritche in Understanding Naturalism, have also thought about such things, and written philosophical resources extensively discussing issues of physicalism, logic, and value. But what is nice is that Lowder provides a detailed, point-by-point refutation against arguments of this sort in a two and half hour video, based on slides he used to prepare for a public debate with Turek.

I am going to start posting again here on Civ by beginning with a relatively short discussion of my definition of metaphysical naturalism. I have discussed some of the conceptual and ontological ways of defining both the “natural” and the “supernatural” in a couple of my previous essays on this blog (see here and here). In those essays I discuss criteria such as physicalism, reductionism, uniformity, and teleology. I think that all of these criteria are useful for articulating some of the ways that we differentiate the natural from the supernatural, but recently I have started to think that an even more minimal definition of naturalism is sufficient to deny one particular supernatural concept, namely the existence of God.

What is big history? This emergent and interdisciplinary field, enriched and pioneered by Dr. David Christian of Macquarie University, encourages a more holistic understanding of human events than does the traditional study of history. While historians are concerned with understanding the past in context, and considering cause and effect in human terms, big historians are concerned with understanding the past not only in its immediate human historical setting, but in the context of scientific and physical laws of nature as well. If history is written by the victor, then big history is written in the stars themselves.

Dr. Christian, bolstered by the support of philanthropist Bill Gates, first injected big history into the public sector with a 2011 TED Talk, providing an 18 minute overview of world history. In this sensational talk, which has garnered more than 5 million views since its publication, Dr. Christian identifies the basic principles of big history, including the concept of Goldilocks conditions and the various “thresholds” of complexity that we observe in the universe. At various moments in the cosmic past, Christian states, certain Goldilocks conditions have come about, in which “not too little, and not too much” of certain components — usually energy or mass — have allowed the universe to reach states of increasing complexity.

Starting at the Big Bang and the first moment of time itself, Christian traces the cause-and-effect of each moment and identifies these thresholds. He highlights the six universal thresholds of complexity as follows:

A normative statement is a claim that expresses value, preference, or obligation. Words like “should” and “ought,” or “good” and “bad,” or even “beautiful” and “ugly” are not merely factual descriptions of the world, but also include underlying judgements. It can be a factual statement that a piece of art consists of certain colors, shapes, and patterns, for example, but that is not the same thing as saying whether a piece of art is pleasant to look at or beautiful. Normative statements investigate different properties pertaining to objects and behavior. Their underlying meaning is not merely descriptive, but also preferential. This distinction is often termed the “is-ought problem.”

One of the major objections made against metaphysical naturalism is that it is unable to account for the truth of normative claims. In particular, apologetic moral arguments often levy the charge that naturalism cannot account for the truth of moral values and imperatives, and that naturalist metaphysics thus entails moral anti-realism. Whether this assertion is defensible is a question that I will investigate later in this blog series. Before that, however, I want to make some key distinctions between “moral” normative statements and other types of normative claims. In particular, a response that I often get, from both theists and atheists alike when using words like “should” and “ought,” is that such words inherently possess moral judgements. I do not think that this interpretation is correct, and accordingly, I am going to lay out certain types of normative statements below that do not necessarily relate to moral judgements, despite their normative character.

As I have been doing research this holiday season on naturalist metaphysics, I have been reading philosopher Jack Ritchie’s Understanding Naturalism. Ritchie, unlike myself, is a non-physicalist naturalist, but I greatly appreciate his open-minded discussion of some of the metaphysical problems posed by physicalism — such as how one can explain things like consciousness, morality, or mathematics in purely physical terms. Ritchie also proposes a number of solutions for how physicalists can respond to these problems.

One solution that Ritchie proposes for explaining apparently non-physical things— like internal subjective experiences —within a purely physical universe is not to argue that the methods of physics can conceptually explain all things, rather than that physics can causally explain all things. This proposal leads to an interesting understanding of the relationship between science and philosophy, and what Ritchie (citing Frank Jackson in From Metaphysics to Ethics) calls “placement problems.”

Ritchie (pg. 133) writes:

“Metaphysical naturalists who call themselves physicalists do not have to endorse the idea that the methods of science and those of philosophy are continuous. Philosophy finds a special role in dealing with … placement problems. Science tells us that everything is physical; the philosopher’s job, then, is to show us how the things that don’t seem physical – minds, meanings, morals – fit into the physical world. The work of placing non-physical things into the physical world is not (or at least need not be considered to be) science or like science in its methods, but a priori metaphysical work … [This] leads to the surprising conclusion that a naturalist should be committed to work that he calls conceptual analysis.”

Personally, I found this approach to be rather interesting, and it also resonated with some of my recent thinking. One thing that strikes me doing research in metaphysical naturalism is just how much of it is abstract “metaphysical” work. That would seem odd, because naturalists are normally thought to eschew metaphysics and rely solely on the methods of science. But that is not so.

A lot of scientists have been criticized for arguing that the scientific method has replaced the need for philosophy in the modern world, and that philosophy is now “dead” or “useless.” Physicist Sean Carroll, however, has criticized this attitude in his post “Physicists Should Stop Saying Silly Things about Philosophy.” Among the complaints against philosophy that Carroll discusses is the following:

“Philosophers care too much about deep-sounding meta-questions, instead of sticking to what can be observed and calculated.”

To which Carroll responds:

“Here we see the unfortunate consequence of a lifetime spent in an academic/educational system that is focused on taking ambitious dreams and crushing them into easily-quantified units of productive work. The idea is apparently that developing a new technique for calculating a certain wave function is an honorable enterprise worthy of support, while trying to understand what wave functions actually are and how they capture reality is a boring waste of time.”

This criticism made me think of Jack Ritchie’s analysis above. The methods of science and philosophy do not need to be continuos. Science can be our primary method for telling us what exists, but we will still need philosophy for describing what it is like. Science is empirical. Philosophy is conceptual.

That is why, here on Civitas Humana philosophy is fully embraced, even among us scientific, physicalist naturalists. We will always need philosophy to deal with the placement problems of what science discovers. Only then can we explain things like consciousness, morality, mathematics, etc. within a purely secular framework.

Cutting philosophy out of the picture will only give advantage to critics of metaphysical naturalism, who delight in posing philosophical problems. But, for the philosophically-minded naturalist, these problems can all be easily addressed. They cannot be addressed, however, if we just ignore the conceptual analysis of philosophy and only study science. So, study philosophy too! It will make you smarter and better equipped to articulate and defend the naturalist worldview!